AC in this 1991 (original owner, 153K miles) has always worked great after replacing evaporator and converting to R134 6 years ago.

Now the AC is coming mostly out of the defroster vents on top of the dash with a little coming out of the side vents on the front of the dash. Nothing is coming out of the center dash vents. A good amount also comes out of the rear seat passenger vent.

Can anyone comment on what the likely problem(s) might be?

Is anyone aware of a good independent AC shop in the Tampa Bay area that knows these cars?

Thank you.